Vehicles such as automobiles that are intended for on-road use are designed to protect the occupants who are travelling in the vehicle. This function is performed in part by the body structure of the vehicle. The body structure may include, as examples, externally visible body panels, a frame, a chassis, a monocoque, a subframe, and/or other types of structures and combinations of such structures.
During an impact of the vehicle with respect to another vehicle or a fixed object, the body structure of the vehicle may be subjected to extreme forces that can cause deformation of the body structure. Certain portions of the body structure may be reinforced to resist deformation. This may be the case, for example, for portions of the vehicle's body structure that surround the passenger compartment of the vehicle. By reinforcing structures surrounding the passenger compartment, intrusion of body structures into the passenger compartment can be reduced. Other portions of a vehicle's body structure may be designed such that they are able to deform in a controlled manner. When these portions of the vehicle's body structure deform, part of the energy of the impact is absorbed by the deformation.
Many vehicle designs include a front beam structure that is designed to absorb energy from impacts involving the front end of the vehicle. The front beam structure is positioned forward of the passenger compartment, and typically includes one or more beams that extend in a longitudinal direction of the vehicle. Each of these beams is configured so that it deforms and shortens during an impact, such as by crushing. The amount of deformation (e.g. longitudinal shortening) that these beams experience during an impact is directly related to the amount of energy that the beams absorb. Thus, a longer beam is typically able to absorb more energy during an impact.